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In the first paper of this series data were presented on the volatility and vapor pressure of eight antioxidants. The present work attempts to show how volatility-affects the performance of an antioxidant, particularly in accelerated aging tests. The usual accelerated tests are of two types: those using closed systems such as the air bomb, the oxygen bomb, and oxygen absorption, and those using open systems such as air oven aging and creep.

Comparable volatility data are presented for three phenolic and five aromatic amine compounds. Vapor pressure curves for the materials are given along with the vapor pressure equations derived from these curves. The equations are used to calculate temperatures at which the eight compounds would have equal vapor pressure. Vapor pressures of each material are calculated at specified temperatures. Data are given for several methods of determining actual losses of antioxidants at several different temperatures and at several different airflows. Surface effects are also studied. In general, all methods give the same relative rating of the eight materials, but quantitative data vary considerably with the method used.

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